Christian rudolph and bernhard priebs



UNITED STATES ATENT Orricw CHRLTIAN RUDOLPH AND BERN HARD PRIEBS, OF OFFEN 3ACH-ON-THE MAIN, GERMANY, ASSIGNORS TO K. OEIILER, OF SAME PLACE.

ORANGE AZO DYE-"STU FF.

SPECIFICATION forming part of Letters Patent No. 395,634, dated January 1, 1889. Application filed June 12, 1888. Serial No. 276,876. (No specimens) To (0 whom it may concern:

Be it known that we, CHRISTIAN RUDOLPH and BERNHARD PRIEBS, subjects of the Emperor of Germany, and residing at Offenbachon-the-Main, Germany, have invented. new and useful Improvements in Orange Colorin Matter, of which the following is a specification;

The method of producing these new orange azo dyes consists of two distinct operations. \Ve first produce a peculiar so-callcd intermediate compound of the formula-- c i nznc mcn,

I on

coo

oni,,N=N i by treating tetrazoditolylchloride with one molecule 9 oresotinic acid. (Bez'Zsfe L'ns Handbook, first edition, page 1458.) In the second operation this intermediate compound is treated with the sodium salt of toluylendiaminesulpho-acid and produces the dye-stuff.

\Ve proceed as follows:

First, method of producing the intermediate compound from fol [din a nd cresotz'm'c acid. 21. 2 pounds of tolidin are dissolved in fortyeight pounds of muriatic acid of 20 Baume, an d five hundred pounds of water cooled with ice and added to a solution of twenty-eight pounds of nitrate of soda in one hundred and fifty pounds of water. This solution of tetrazoclitolylchloride is allowed to run slowly into a solution of 15.2 pounds of E cresotinic acid and twenty pounds of soda in three hundred pounds of water. The intermediate compound precipitates slowly as voluminous yellow-brown flakes, and is filtered oft.

Second, production of the clye-stujj-A solution of twenty-three pounds of the sodium salt of toluylendiaminesulpho-acid and six, pounds of soda in three hundred pounds of water is prepared, and the intermediate compound above obtained is added, to it. The formation of the dye-stuff begins at once. It is filtered olii', pressed, and dried as soon as the reaction is finished.

The dye-stint is a red-brown powder, which dissolves easily in hot water. The solution in concentrated sulphuric acid is violet-red.

In the aliove-dcscribed process it is possible to substitute the 7 cresotinic acid (Bc dsfcins Ilamlboolt, page 1455)) for the 9 acid without changing the result. In both cases an orange dye-stuff is obtained which is equally suitable for dyeing cotton without mordant.

Havingthus described our invention and the manner of employing the same, what we claim, and wish to have secured to us by Letters Patent oi the United States of America, 1s

The orange azo dye-stuff herein described, produced from tolidin by diazotation and subsequent heatingwith cresotin acid and toluylendiami'nesulpho-aeid, and which is a redbrown powder which. dissolves easily in hot water, and the solution of which in concen trated sulphuric acid is violet-red.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

CHRISTIAN RUDOLPH.

ZERNHARD PRIEBS. \Vitnesses as to Christian Rudolph:

J OSEPH PATRI K, ALVESTO S. IIOGUE. \Vitnesses as to Bernhard Priebs:

J AOOB MUELLER, J EAN GRUND. 

